An elevating tailgate or lift platform for a motor vehicle such as a flat bed truck usually is carried by a frame suspended from the rear of the truck bed and comprises lift arms, the platform itself and power means such as a hydraulic cylinder by which the lift arms are swung from a lower or loading position of the platform, wherein it is substantially at ground level, to an upper or unloading position where the platform remains horizontal but is substantially at the level of the truck bed. In some of these devices the elevating platform is so pivotally mounted on the ends of the lift arms that it can be swung upwardly into a vertical position at the back of the truck bed and thus can function as a tailgate after it has been used for lifting heavy items from ground level up to the truck bed. It is to this latter type of device that the instant invention is directed.
Some prior art elevating platforms and/or tailgates can be swung from their upper, unloading position where they are horizontal to a vertical tailgate position by being manually moved from the one position to the other. However, in order that such a device may lift relatively heavy loads, the platform itself usually is quite massive and swinging the platform from its upper horizontal position at the level of the truck bed to a vertical, tailgate position manually is rather difficult as well as being somewhat dangerous. Even when safety chains or locks are provided, if the operator must first swing the platform vertically to tailgate position he then has to hold it in that position with one hand while he engages the safety lock or chain to prevent the tailgate from falling downwardly.
It is, therefore, the principal object of the instant invention to provide an elevating tailgate which not only is power actuated for elevating massive items from ground level to the truck bed level but also is power actuated to swing from its upper horizontal unloading position to a vertical tailgate position.